Re: [dpdk-dev] [PATCH v1] net/tap: allow user MAC to be passed as args

[Pascal Mazon <pascal.mazon@6wind.com>]

Acked-by: Pascal Mazon <pascal.mazon@6wind.com>


On 12/02/2018 15:44, Vipin Varghese wrote:
> Allow TAP PMD to pass user desired MAC address as argument.
> The argument value is processed as string delimited by  ':',
> is parsed and converted to HEX MAC address after validation.
>
> Signed-off-by: Vipin Varghese <vipin.varghese@intel.com>
> Signed-off-by: Pascal Mazon <pascal.mazon@6wind.com>
> ---
>
> Changes:
>  - seggrated the function for hex sting validation - Ferruh
>  - Fixed the logic lookup for MAC address
> ---
>  drivers/net/tap/rte_eth_tap.c | 75 +++++++++++++++++++++++++++++++++----------
>  1 file changed, 58 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/net/tap/rte_eth_tap.c b/drivers/net/tap/rte_eth_tap.c
> index 9d39384..5f67d51 100644
> --- a/drivers/net/tap/rte_eth_tap.c
> +++ b/drivers/net/tap/rte_eth_tap.c
> @@ -48,6 +48,10 @@
>  #define ETH_TAP_MAC_ARG         "mac"
>  #define ETH_TAP_MAC_FIXED       "fixed"
>  
> +#define ETH_TAP_USR_MAC_FMT     "xx:xx:xx:xx:xx:xx"
> +#define ETH_TAP_CMP_MAC_FMT     "0123456789ABCDEFabcdef"
> +#define ETH_TAP_MAC_ARG_FMT     ETH_TAP_MAC_FIXED "|" ETH_TAP_USR_MAC_FMT
> +
>  static struct rte_vdev_driver pmd_tap_drv;
>  
>  static const char *valid_arguments[] = {
> @@ -1335,7 +1339,7 @@ enum ioctl_mode {
>  
>  static int
>  eth_dev_tap_create(struct rte_vdev_device *vdev, char *tap_name,
> -		   char *remote_iface, int fixed_mac_type)
> +		   char *remote_iface, struct ether_addr *mac_addr)
>  {
>  	int numa_node = rte_socket_id();
>  	struct rte_eth_dev *dev;
> @@ -1397,16 +1401,10 @@ enum ioctl_mode {
>  		pmd->txq[i].fd = -1;
>  	}
>  
> -	if (fixed_mac_type) {
> -		/* fixed mac = 00:64:74:61:70:<iface_idx> */
> -		static int iface_idx;
> -		char mac[ETHER_ADDR_LEN] = "\0dtap";
> -
> -		mac[ETHER_ADDR_LEN - 1] = iface_idx++;
> -		rte_memcpy(&pmd->eth_addr, mac, ETHER_ADDR_LEN);
> -	} else {
> +	if (is_zero_ether_addr(mac_addr))
>  		eth_random_addr((uint8_t *)&pmd->eth_addr);
> -	}
> +	else
> +		rte_memcpy(&pmd->eth_addr, mac_addr, sizeof(mac_addr));
>  
>  	/* Immediately create the netdevice (this will create the 1st queue). */
>  	/* rx queue */
> @@ -1567,15 +1565,58 @@ enum ioctl_mode {
>  	return 0;
>  }
>  
> +static int parse_user_mac(struct ether_addr *user_mac,
> +		const char *value)
> +{
> +	unsigned int index = 0;
> +	char mac_temp[strlen(ETH_TAP_USR_MAC_FMT) + 1], *mac_byte = NULL;
> +
> +	if (user_mac == NULL || value == NULL)
> +		return 0;
> +
> +	snprintf(mac_temp, sizeof(mac_temp), "%s", value);
> +	mac_byte = strtok(mac_temp, ":");
> +
> +	while ((mac_byte != NULL) &&
> +			(strlen(mac_byte) <= 2) &&
> +			(strlen(mac_byte) == strspn(mac_byte,
> +					ETH_TAP_CMP_MAC_FMT))) {
> +		user_mac->addr_bytes[index++] = strtoul(mac_byte, NULL, 16);
> +		mac_byte = strtok(NULL, ":");
> +	}
> +
> +	return index;
> +}
> +
>  static int
>  set_mac_type(const char *key __rte_unused,
>  	     const char *value,
>  	     void *extra_args)
>  {
> -	if (value &&
> -	    !strncasecmp(ETH_TAP_MAC_FIXED, value, strlen(ETH_TAP_MAC_FIXED)))
> -		*(int *)extra_args = 1;
> +	struct ether_addr *user_mac = extra_args;
> +
> +	if (!value)
> +		return 0;
> +
> +	if (!strncasecmp(ETH_TAP_MAC_FIXED, value, strlen(ETH_TAP_MAC_FIXED))) {
> +		static int iface_idx;
> +
> +		/* fixed mac = 00:64:74:61:70:<iface_idx> */
> +		memcpy((char *)user_mac->addr_bytes, "\0dtap", ETHER_ADDR_LEN);
> +		user_mac->addr_bytes[ETHER_ADDR_LEN - 1] = iface_idx++ + '0';
> +		goto success;
> +	}
> +
> +	if (parse_user_mac(user_mac, value) != 6)
> +		goto error;
> +success:
> +	RTE_LOG(DEBUG, PMD, "TAP user MAC param (%s)\n", value);
>  	return 0;
> +
> +error:
> +	RTE_LOG(ERR, PMD, "TAP user MAC (%s) is not in format (%s|%s)\n",
> +		value, ETH_TAP_MAC_FIXED, ETH_TAP_USR_MAC_FMT);
> +	return -1;
>  }
>  
>  /* Open a TAP interface device.
> @@ -1589,7 +1630,7 @@ enum ioctl_mode {
>  	int speed;
>  	char tap_name[RTE_ETH_NAME_MAX_LEN];
>  	char remote_iface[RTE_ETH_NAME_MAX_LEN];
> -	int fixed_mac_type = 0;
> +	struct ether_addr user_mac;
>  
>  	name = rte_vdev_device_name(dev);
>  	params = rte_vdev_device_args(dev);
> @@ -1626,7 +1667,7 @@ enum ioctl_mode {
>  				ret = rte_kvargs_process(kvlist,
>  							 ETH_TAP_MAC_ARG,
>  							 &set_mac_type,
> -							 &fixed_mac_type);
> +							 &user_mac);
>  				if (ret == -1)
>  					goto leave;
>  			}
> @@ -1637,7 +1678,7 @@ enum ioctl_mode {
>  	RTE_LOG(NOTICE, PMD, "Initializing pmd_tap for %s as %s\n",
>  		name, tap_name);
>  
> -	ret = eth_dev_tap_create(dev, tap_name, remote_iface, fixed_mac_type);
> +	ret = eth_dev_tap_create(dev, tap_name, remote_iface, &user_mac);
>  
>  leave:
>  	if (ret == -1) {
> @@ -1701,5 +1742,5 @@ enum ioctl_mode {
>  RTE_PMD_REGISTER_ALIAS(net_tap, eth_tap);
>  RTE_PMD_REGISTER_PARAM_STRING(net_tap,
>  			      ETH_TAP_IFACE_ARG "=<string> "
> -			      ETH_TAP_MAC_ARG "=" ETH_TAP_MAC_FIXED " "
> +			      ETH_TAP_MAC_ARG "=" ETH_TAP_MAC_ARG_FMT " "
>  			      ETH_TAP_REMOTE_ARG "=<string>");